Pressure-gage for pneumatic tires.



G. R. TWITGHELL.

PRESSURE GAGE FOB PNEUMATIG TIRES.

APPLIGATION Hmm 00129, moa.

927,298. d Panwgly 6,1909.

UJJLLLU Dlflljli@ fillhltl UIJJDJUUEM CHARLES R. TWITOHELL, OF LOSANGELES, CALIFORNIA.

PRESSURE-GAGE FOR PNEUMATIC TIRES.

To all whom it may concern:

e it known that l', Cnannns lt. Twirci-rma., of Los Angeles, in thecounty of Los Angeles and State of California, have in vented certainnew and useful lmprovements in Pressure-Gages for Pneumatic 'lliresg andl do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

rf he primary object of this invention is to provide a device forreadily ascertaining the pressui'e within a pneumatic tire, which devicewill be simple and compact, and capable of being readily applied to theair valve of a tire.

The invention will be hereinafter fully set forth and particularlypointed out :inthe el aims.

ln the accompanying drawing: Figure l is a. view in perspective. Fig. 2is a vertical longitruliiuil sectional view. Fig. 3 is a cross sectionalview. Fig. 4l, is an end view.

Referring to the drawings, l designates a housing which is preferably inthe form of a tubular body in one end of which is formed a narrow slot,while the other end is open. lllithin this open end of the housing isfitted a ring-like packing 2l of leather or other suitable material,which packing has a central opening through which projects a fixed part,shown in the form of an anvil This anvil is preferably composed of apiece of metal bent baclr upon itself, and

secured at its ends to a fixed washer t within the housing near the openend thereof. The packing 2 forms a seat for the valve-casing of apneumatic tire, the valve itself being unseated by theprojecting end ofthe anvil.

5 designates a gage bar located within the housing and projectingthrough the slot in one end thereof. At the inner end of this bar is apiston head G which is shown in the form of a cupped-washer againstwhich bears one end of a coiled spring 7 which normally holds the gagebar retracted, the other end of such spring bearing against the slottedend of the housing. The inward movement of the gage bar is limited bythe stop formed by washer 4C.

`When it is desired to ascertain the pressure within a pneumatic tirethe operator positions the open end of the tubular body or housing overthe outer end of the casing Specification of Letters Patent.

Application filed October 9, 1908.

Patented July 6, 1909 Serial No. 456,953.

of the air valve of such tire. ln so doing, the anvil, or fixed part, ofthe device engages the i,)rojccting end of the valve and effects theunseating of the latter. lhe air pressure within the tire will actagainst the Yasher or piston head of the gage bar and immediately forcethe latter outward as against the tension of spring 7 rlhis gage barcarries on one side a series of marks of graduation, as shown at 9,iiulicating pounds pressure per square inch, and hence as the bar .isforced outward the pressure existing within the tire is indicated by themarks of graduation. Immediately upon removing the device the valve ofthe tire will, of course, automatically resume its seat. ln this way, bymeans of a very simple and inexpensive device, capable of being carriedin the pocket of the user, the pressure within a pneumatic tire may beascertained without danger of unduly lessening such pressure.

By means of this device all users of pneu matic tires are enabled toguard against over charging which frequently results in serious loss.

l claim as my invention:

l. As an article of manufacture, a pressure gage for pneumatic tirescomprising a housing open at its inner end, which latter is designed tofit over and inclose the casing of the air valve of a pneun'iatic tire,means at such end for fitting against and unseating such air valve, aspring-held gage-bar within said housing and projecting through anopening in the outer end thereof, and a piston-head at the inner end ofsaid gagebar.

Q. As an article of manufacture, a pressure gage for pneumatic tirescomprising a housing open at one end, a seat at such end for fittingagainst the air-valve casing of a pneumatic tire, means also at such endfor unseating such airfalve, and a spring-held gagesbar within saidhousing and projecting through an opening in the outer end thereof, saidgagebar having a piston-head at its inner end.

3. As an article of manufacture, a pressure gage for pneumatic tirescomprising a housing open at one end, a scat at such end for fittingagainst the air-valve casing of a pneumatic tire, said seat having acentral opening, a fixed part extended through said opening forunseating such air-valve, and a springheld gage bar located within saidhousing and projecting through an opening in the outer end thereof, saidgage-bar having a piston head at its inner end.

4. As an article of manufacture, a tubular body open at one end andhaving a slot in its other end, a gage bar Within said body extendedthrough said slot, a piston-head at the inner end of said gage-bar, aspring on said gage bar, a stop for limiting the in- 13 ward movement ofthe latter, and a fixed part Within the open end of said body foreffecting the unseating of the air valve of a pneumatic tire.

In testimony whereof, I have signed this specification in the presenceof two sub- 1.3

scribing Witnesses.

CHARLES R. TVVITCHELL. Witnesses FRED. W. NASH, M. CoLYnR.

